\begin{tikzpicture}
  \begin{scope}[x=0.7cm, y=0.7cm, step=0.7cm, thick]
    \board{6}{6};  
    \qb{(3,3)};
    \qb{(4,3)};
    \qb{(5,5)};
    \qw{(1,3)};
    \qw{(3,1)};
    \qw{(6,6)};
    \arrow{(1, 4)};
    \arrow{(2, 4)};
    \arrow{(3, 4)};
    \arrow{(3, 5)};
    \arrow{(3, 6)};
    \arrow{(4, 5)};
    \arrow{(4, 6)};
    \arrow{(4, 2)};
    \arrow{(4, 1)};
    \arrow{(5, 2)};
    \arrow{(5, 4)};
    \arrow{(6, 3)};
    \arrow{(6, 2)};
    \arrow{(6, 4)};
  \end{scope}
\end{tikzpicture}

% 6 . . X X . B
% 5 . . X X W .
% 4 X X X . X X
% 3 B . W W . X
% 2 . . . X X X
% 1 . . B X . .
%   A B C D E F 
% N-class
